Urban traffic lifeline construction method and system under extreme rainstorm weather

The invention relates to an urban traffic lifeline construction method and system under extreme rainstorm weather. The method comprises the following steps: carrying out rainstorm waterlogging simulation; removing inland inundation failure road sections, carrying out traffic simulation on the retained effective road network, and obtaining severely congested road sections; according to the traffic accident data, analyzing urban road accident black spots, and obtaining high-risk road sections; recognizing an initial traffic lifeline set in combination with results of rainstorm waterlogging simulation, traffic simulation and urban road accident black spot analysis; and judging whether the traffic lifeline set meets expected requirements or not, if so, outputting an urban traffic lifeline set under extreme rainstorm weather, and if not, perfecting drainage and waterlogging prevention facilities and re-identifying the corrected traffic lifeline set until the corrected traffic lifeline set meets the requirements by